Rewrite and validate reap_oldest; don't bump active when querying last_active
Reformatting only, no functional change
Fix dirty replacement to update and to correctly adjust cache size
Add garbage_collect after M:F initializes new datum pid
More efficient random data selection, no unit test yet
Verify and correct rand and rand_key with unit tests
Optimize tail of rand when no more Datum_Pids are needed
Merge pull request #5 from jaynel/selective-receive

Rewrite and validate reap_oldest